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See detailResponse of plant functional traits during the restoration of calcareous grasslands from forest stands
Piqueray, Julien; Ferroni, Lucia; Delescaille, Louis-Marie et al

in Ecological Indicators (in press)

In this survey, we studied the response of plant functional traits to calcareous grassland restoration in the Calestienne region, Southern Belgium (restoration protocol: forest clear-cutting followed by ... [more ▼]

In this survey, we studied the response of plant functional traits to calcareous grassland restoration in the Calestienne region, Southern Belgium (restoration protocol: forest clear-cutting followed by grazing at all sites). We considered traits related to dispersal, establishment, and persistence that integrate the main challenges of plants to re-establish and survive in restored areas. Functional traits were compiled from databases and compared among (i) pre-restoration and young restoration forests; (ii) restoration areas of different ages; and (iii) old restorations and reference grasslands. The following questions were addressed: (i) What is the early response (2-4 years) in terms of plant functional trait following one restorative clear-cut event? (ii) What plants functional trait responses occur from restorative management (i.e. sheep and goat grazing)? (iii) Which differences still persist between the oldest restored parcels (10-15 years), and the historical reference grasslands? Forest clear-cuts induced several changes among functional traits, including decreased mean seed mass and certain vegetative traits (i.e. decreased phanerophytes, branching species; and increased short lifespan species i.e. annuals and biennials). During restorative management, clonal, epizoochorous and autumn germinating species were favored. Despite numerous other changes during this phase, many differences remained compared to reference grasslands. In particular, geophytes, mycorrhizal and evergreen species abundance were not approaching reference grassland values. The observed pattern helped to draw inferences on the possible mechanisms operating under vegetation recovery following restorative forest clear-cut and subsequent management were identified and described in this study. Results indicated grazing was an important factor, which increased epizoochorous species, and autumn germinating taxa that filled niches in vegetation opened by summer grazing animals. Finally, differences between old restoration and reference grasslands emphasized that management should focus on reduction in soil fertility, and geophyte rhizomatous grasses. Long-term monitoring is vital to assess if management plans are effective in the complete restoration of species functional trait assemblages. [less ▲]

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See detailA global analysis of Spitzer and new HARPS data confirms the loneliness and metal-richness of GJ 436 b
Lanotte, Audrey ULg; Gillon, Michaël ULg; Demory, B.-O. et al

in Astronomy and Astrophysics (in press)

Context. GJ 436b is one of the few transiting warm Neptunes for which a detailed characterisation of the atmosphere is possible, whereas its non-negligible orbital eccentricity calls for further ... [more ▼]

Context. GJ 436b is one of the few transiting warm Neptunes for which a detailed characterisation of the atmosphere is possible, whereas its non-negligible orbital eccentricity calls for further investigation. Independent analyses of several individual datasets obtained with Spitzer have led to contradicting results attributed to the different techniques used to treat the instrumental effects. Aims. We aim at investigating these previous controversial results and developing our knowledge of the system based on the full Spitzer photometry dataset combined with new Doppler measurements obtained with the HARPS spectrograph. We also want to search for additional planets. Methods. We optimise aperture photometry techniques and the photometric deconvolution algorithm DECPHOT to improve the data reduction of the Spitzer photometry spanning wavelengths from 3-24 {\mu}m. Adding the high precision HARPS radial velocity data, we undertake a Bayesian global analysis of the system considering both instrumental and stellar effects on the flux variation. Results. We present a refined radius estimate of RP=4.10 +/- 0.16 R_Earth, mass MP=25.4 +/- 2.1 M_Earth and eccentricity e= 0.162 +/- 0.004 for GJ 436b. Our measured transit depths remain constant in time and wavelength, in disagreement with the results of previous studies. In addition, we find that the post-occultation flare-like structure at 3.6 {\mu}m that led to divergent results on the occultation depth measurement is spurious. We obtain occultation depths at 3.6, 5.8, and 8.0 {\mu}m that are shallower than in previous works, in particular at 3.6 {\mu}m. However, these depths still appear consistent with a metal-rich atmosphere depleted in methane and enhanced in CO/CO2, although perhaps less than previously thought. We find no evidence for a potential planetary companion, stellar activity, nor for a stellar spin-orbit misalignment. [ABRIDGED] [less ▲]

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See detailIntegrated bio-chemostratigraphical correlations and climatic evolution across the Danian-Selandian boundary at low latitudes
Storme, Jean-Yves ULg; Steurbaut, Etienne; Devleeschouwer, Xavier et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (in press)

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See detailDevelopment by the sol–gel process of highly dispersed Ni–Cu/SiO2 xerogel catalysts for selective 1,2-dichloroethane hydrodechlorination into ethylene
Pirard, Sophie ULg; Mahy, Julien ULg; Pirard, Jean-Paul ULg et al

in Microporous and Mesoporous Materials (in press)

Ni–Cu/SiO2 xerogel catalysts have been synthesized by cogelation of industrial tetraethoxysilane (Dynasil) and chelates of Ni and Cu with industrial 3-(2-aminoethylamino)propyltrimethoxysilane (Dynasylan ... [more ▼]

Ni–Cu/SiO2 xerogel catalysts have been synthesized by cogelation of industrial tetraethoxysilane (Dynasil) and chelates of Ni and Cu with industrial 3-(2-aminoethylamino)propyltrimethoxysilane (Dynasylan DAMO) in industrial ethanol denatured with diethyl phthalate. Despite the use of industrial grade reagents, highly dispersed bimetallic Ni–Cu/SiO2 xerogel catalysts were obtained. These samples are composed of completely accessible Ni–Cu alloy crystallites with sizes of 1.6–3.4 nm located inside silica particles exhibiting a monodisperse microporous distribution. It appears that the bimetallic complex acts as a nucleation agent in the formation of silica particles. The combination of results obtained from the calculation of the metal ratio in catalysts, H2 chemisorption and transmission electron microscopy allowed calculating the surface composition of the nickel–copper particles in Ni–Cu/SiO2 cogelled xerogel catalysts. Values obtained indicate a very pronounced surface enrichment with copper. While 1,2-dichloroethane hydrodechlorination over pure nickel mainly produces ethane, increasing copper content in bimetallic catalysts results in an increase in ethylene selectivity. The specific consumption rate of 1,2-dichloroethane decreases when copper loading increases. The turnover frequency, that is, the number of catalytic cycle per active site (nickel atom and its surrounding copper atoms) and per second, seems to be independent of surface composition of alloy particles. [less ▲]

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See detailSemiótica de la acción: textualización y notación
Dondero, Maria Giulia ULg

in Tópicos del seminario (2015), 31

Our essay focuses on some methodological issues concerning the semiotic analysis of practice. We will initially retrace the debate about the epistemological relationship between text and action, outlining ... [more ▼]

Our essay focuses on some methodological issues concerning the semiotic analysis of practice. We will initially retrace the debate about the epistemological relationship between text and action, outlining the forms of enunciative praxis through different levels of pertinence analysis. Secondly, we propose the concept of ‘textualization’ as a mediation between text and action: textualizations (photographs, videos, notes) organize and represent practices which are in themselves ephemeral and elusive. Finally, we will consider the textual diagrammatization that we call ‘notation’: this analytical form of mediation between text and practice does not have the same status of in-vivo textualisations, but it works like an ex-post reconstruction which highlights the main gestures and exchanges while performing their grammaticalization. A more general aim of this essay is an enquiry into the legitimate objects of textual semiotics: what are the objects that it can analyze without betraying its principle of immanence, but also without being confined to it and, as a consequence, being unable to analyze practices and respond to topical questions on social issues and on the research in the human sciences? [less ▲]

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See detailQuand la clinique bouscule les concepts
Englebert, Jérôme ULg

Scientific conference (2015, February 11)

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See detailLa démocratie sous expertise. Médias, think tanks et privatisation du débat européen (en préparation, parution début 2015)
Geuens, Geoffrey ULg

Book published by Éditions du Croquant, coll. "Savoir / Agir" (2015)

L’ouvrage questionne la genèse des think tanks eurofédéralistes participant à la fabrication et à la légitimation des politiques d’intégration, avant de s’intéresser à ces autres agents sociaux de ... [more ▼]

L’ouvrage questionne la genèse des think tanks eurofédéralistes participant à la fabrication et à la légitimation des politiques d’intégration, avant de s’intéresser à ces autres agents sociaux de production et de diffusion de la pensée européenne que sont notamment les correspondants bruxellois et éditorialistes de quelques grands médias européens. L’ouvrage montre combien le discours journalistique sur l’Europe et le discours de certains « spécialistes » des questions européennes, qui trouve aussi à s’exprimer dans l’espace médiatique, sont la plupart du temps limités à quelques expressions stéréotypées et argumentaires clichés s’expliquant autant par la position occupée dans le champ du pouvoir par les agents qui s’en font les relais que par les dispositions de ces mêmes agents sociaux à l’égard du « projet européen ». [less ▲]

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See detailEffects of low dose endosulfan exposure on brain neurotransmitter levels in the African clawed frog Xenopus laevis
Preud'Homme, Valérie; Milla, Sylvain; Gillardin, Virginie et al

in Chemosphere (2015), 120(2), 357-364

Understanding the impact of pesticides in amphibians is of growing concern to assess the causes of their decline. Among pesticides, endosulfan belongs to one of the potential sources of danger because of ... [more ▼]

Understanding the impact of pesticides in amphibians is of growing concern to assess the causes of their decline. Among pesticides, endosulfan belongs to one of the potential sources of danger because of its wide use and known effects, particularly neurotoxic, on a variety of organisms. However, the effect of endosulfan was not yet evaluated on amphibians at levels encompassing simultaneously brain neurotransmitters and behavioural endpoints. In this context, tadpoles of the African clawed frog Xenopus laevis were submitted to four treatments during 27 d: one control, one ethanol control, and two low environmental concentrations of endosulfan (0.1 and 1 μg L−1). Endosulfan induced a significant increase of brain serotonin level at both concentrations and a significant increase of brain dopamine and GABA levels at the lower exposure but acetylcholinesterase activity was not modified by the treatment. The gene coding for the GABA transporter 1 was up-regulated in endosulfan contaminated tadpoles while the expression of other genes coding for the neurotransmitter receptors or for the enzymes involved in their metabolic pathways was not significantly modified by endosulfan exposure. Endosulfan also affected foraging, and locomotion in links with the results of the physiological assays, but no effects were seen on growth. These results show that low environmental concentrations of endosulfan can induce adverse responses in X. laevis tadpoles. At a broader perspective, this suggests that more research using and linking multiple markers should be used to understand the complex mode of action of pollutants. [less ▲]

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See detailEffect of stress path on the miniaturizatio size effect for nickel polycrystals
Keller, Clement; Hug, Eric; Duchene, Laurent ULg et al

Conference (2015, January 04)

The mechanical behavior of mettalic materials deeply depends on the size of samples. For specimen dimensions de creasing from a few millimeters to a few micrometers, the general observed trend is a ... [more ▼]

The mechanical behavior of mettalic materials deeply depends on the size of samples. For specimen dimensions de creasing from a few millimeters to a few micrometers, the general observed trend is a softening of the mechanical behavior in tension which affects the stress level and the strain hardening. This effect is triggered by the derease of the number of grains across the thickness ( also called thickness"t" over grain size "d" ratio). The objective of this work is to provide new experimental results in order to analyse the miniaturization size effects for various stress paths without strain gradients across the thickness of the samples. To this aim, experimental tensil tests, large tensile tests and shear tests have been performed on Ni sheets ( 0.5mm) with various grain sizes ensuring different t/d ratios. Results show that the miniaturization softening is affected by triaxiality, the larger is this parameter, the lower is the mechanicval softening. These features seem to be linked to surface effects which are larger for low triaxiality stress paths. Attempts of numerical simulations using strain gradient crystal plasticity model are also performed to confirm the role played by surface effects. [less ▲]

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See detailA new species of Groenlandaspis Heintz, 1932 (Placodermi, Arthrodira) from the Famennian (Late Devonian) of Belgium
Olive, Sébastien ULg; Prestianni, Cyrille; Dupret, Vincent

in Journal of Vertebrate Paleontology (2015), 35(5),

A new species of the phlyctaeniid arthrodire genus Groenlandaspis from the upper Famennian of Belgium is described. The remains of Groenlandaspis potyi sp. nov. consist of dissociated thoracic armor ... [more ▼]

A new species of the phlyctaeniid arthrodire genus Groenlandaspis from the upper Famennian of Belgium is described. The remains of Groenlandaspis potyi sp. nov. consist of dissociated thoracic armor elements, but the specimen designed to be the holotype displays the median dorsal, anterior and posterior dorsolateral plates in connection. Though incomplete, the new species is characterized by an equilateral triangle-shaped median dorsal plate, a protruding posterodorsal apron of the posterior dorsolateral plate behind the overlap area for the median dorsal plate, and an overall lack of ornamentation. Groenlandaspis potyi sp. nov. constitutes the second occurrence of a Groenlandaspis species in continental Europe after the description of Groenlandaspis thorezi from upper Famennian quarries of Belgium. Another probable new species of Groenlandaspis is also described, though of unknown locality and horizon; it can however be deduced from the upper Famennian of Belgium without more precision. Together with some unpublished material of groenlandaspidids from the Famennian tetrapod-bearing locality of Strud, this material highlights the richness of the Groenlandaspididae diversity in Belgium. The discovery of Groenlandaspis potyi sp. nov. in Belgium reinforces the Famennian global distribution of this widespread genus during this period. Also, since those organisms have possibly been considered as non-marine indicators, this material is another argument pleading for close relationships between Euramerica and Gondwana around the Frasnian-Famennian boundary. [less ▲]

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See detailElsvier, Computers in Industry, Special Issue on Natural Language Processing and Text Analytics in Industry
Ittoo, Ashwin ULg; Bosh, v.d., Antal; Nguyen, Le Minh

Book published by Elsevier (2015)

Detailed reference viewed: 23 (5 ULg)
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See detail"Des muets qui veulent parler". Lectures politiques, des Temps Modernes à L'Idiot de la famille
Cormann, Grégory ULg

in Bolmain, Thomas; Cormann, Grégory (Eds.) Politiques de la littérature. Bourdieu, Sartre, Foucault (2015)

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See detailRitournelles et territoires professionnels. Le cas des conseillers emploi
Orianne, Jean-François ULg

in Langage et Société (2015)

L’objectif de ce texte est d’utiliser le concept de ritournelle pour analyser la formation d’un groupe professionnel dans le champ des politiques d’emploi en Belgique : les conseillers emploi du FOREM ... [more ▼]

L’objectif de ce texte est d’utiliser le concept de ritournelle pour analyser la formation d’un groupe professionnel dans le champ des politiques d’emploi en Belgique : les conseillers emploi du FOREM. L’auteur commence par définir et opérationnaliser le concept, emprunté à Deleuze et Guattari, en suivant les apports des théories de la communication réflexive. Il esquisse brièvement le contexte politique et institutionnel au sein duquel le groupe professionnel apparaît. Ensuite, il analyse trois ritournelles professionnelles, trois procédés de territorialisation des identités professionnelles des conseillers emploi. Il précise, en conclusion, la complémentarité du concept de ritournelle avec celui de rhétorique professionnelle. [less ▲]

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See detailLa conception d’un programme de formation pédagogique pour des enseignants du supérieur : une démarche à insérer dans un cadre de développement professionnel
Poumay, Marianne ULg

in Daele, Amaury; Sylvestre, Emmanuel (Eds.) Le conseil pédagogique dans l’enseignement supérieur - Cadres de référence, outils de travail et de développement (2015)

Elaborer un programme de formation pour les enseignants est souvent le premier réflexe d’une cellule de conseillers pédagogiques nouvellement créée au sein d’une institution d’enseignement supérieur. Un ... [more ▼]

Elaborer un programme de formation pour les enseignants est souvent le premier réflexe d’une cellule de conseillers pédagogiques nouvellement créée au sein d’une institution d’enseignement supérieur. Un tel programme permet en effet une première sensibilisation aux questions d’apprentissage, une première étape dans ce qui pourrait devenir une réelle politique de développment professionnel pour les enseignants. Mais quelles sont les limites d’une telle approche ? Quelles sont ses conditions d’efficacité ? Au vu de quelques expériences européennes et notamment celle de l’université de Liège (Belgique), ce chapitre tente d’éclairer les défis majeurs qui attendent les conseillers pédagogiques au détour de leur conception d’un tel programme. [less ▲]

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See detailMamlūk Cairo: A Crossroad for Embassies
Bauden, Frédéric ULg; Dekkiche, Malika

Book published by Brill Academic Publishers (2015)

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See detailManuel. Les contrats spéciaux
Kohl, Benoît ULg; Burette, Caroline ULg; Daenen, Thomas et al

Book published by Larcier (2015)

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See detailLeibniz
Bouquiaux, Laurence ULg

in Bouaniche, Arnaud; Leclercq, Jean (Eds.) Une histoire de la philosophie (2015)

Detailed reference viewed: 7 (0 ULg)